It is known in the art for hydraulic dampers to include a hydraulic compression stop assembly for generating an additional damping force over a predefined section of the piston rod travel during a compression stroke.
An example of such a hydraulic damper is disclosed in international patent application publication no. WO2016146660 which discloses a hydraulic stop member comprising a cup-shaped body, which is adapted to be mounted in a compression chamber. The cup-shaped body is open at its top end facing towards the piston of the shock-absorber, and comprises a side wall and a bottom wall which define, along with the plunger, a working chamber. The side wall and the bottom wall are made as separate pieces and are connected to each other by force-fitting. The side wall has axial channels formed on its inner surface configured to allow the damping fluid to flow axially out of the working chamber. Furthermore, the cup-shaped body has an annular passage, which is in fluid communication with the portion of the compression chamber underneath the bottom wall of the hydraulic stop member.
Another example of such a hydraulic damper is disclosed in international patent application publication no. WO2016126776 which discloses a shock absorber having a hydraulic compression stop including a piston and a sleeve. The sleeve has an open end for receiving the piston and a flow groove that extends longitudinally along an inner surface of the sleeve.
Although hydraulic compression stop assemblies of this kind provide versatile tuning opportunities for shaping damping force characteristics at the very high velocities that may occur during the compression stroke (e.g., while a vehicle hits an obstacle), forces can increase rapidly leading even to damage of the internal components of the damper. Accordingly, there is a need for improvements to hydraulic damper assemblies.